General principles

Data-centric : The pages are the data. They contain semantic only, not how to display them.
Display is performed automatically once the pages are loaded, by parsing the semantic tags/classes/attributes contained in the page
. These can be about places, people, time, etc.

Contextual : Display rendering not only takes into account the semantic tags/classes/attributes,
but also the ways they are assembled. For example a month tag can be resolved as in the context of a previous year tag.